Removes grout, mortar and other stains. Suitable for indoor and outdoor use.
Monestir, who make the sealant, recommend you use Sanet diluted 1:10 (we would advise trying 1:20 first). This is a product specifically for removing dried grout from surfaces, including cement tiles. As it is a very strong product, and as we normally recommend using only gentle products on our tiles, you should try a test area first and leave it for a while to make sure everything is fine.
Dilute the Sanet (1:20 or 1:10), making sure your skin and eyes are protected, and apply with a washing up sponge (the ones with a green scrubby bit on one side and a sponge on the other). Just be careful not to scratch the tiles - it is best to test on an inconspicuous tile first - and wipe the tiles immediately with a clean wet sponge as you go, constantly changing both the solution and the rinsing water, so you are working with clean scrubber and sponge at all times. ie, you will need to mix up more solution and change the rinsing water as you go.